[Qemu-block] [PATCH v2] configure: Work-around a bug in libiscsi 1.9.0 when used in gnu99 mode

[Thomas Huth]

The header "scsi-lowlevel.h" of libiscsi 1.9.0 contains some bad
"inline" prototype definitions which GCC refuses to compile in its
gnu99 mode:

In file included from block/iscsi.c:52:0:
/usr/include/iscsi/scsi-lowlevel.h:810:13: error: inline function
‘scsi_set_uint16’ declared but never defined [-Werror]
 inline void scsi_set_uint16(unsigned char *c, uint16_t val);
             ^
/usr/include/iscsi/scsi-lowlevel.h:809:13: error: inline function
‘scsi_set_uint32’ declared but never defined [-Werror]
 inline void scsi_set_uint32(unsigned char *c, uint32_t val);
             ^

This has been fixed by upstream libiscsi in version 1.10.0 (see
https://github.com/sahlberg/libiscsi/commit/7692027d6c11 ), but
since we still want to support 1.9.0 for CentOS 7 / RHEL7, we
have to work-around the issue by compiling with "-Wno-error"
in this case instead.

Suggested-by: Daniel P. Berrangé <address@hidden>
Signed-off-by: Thomas Huth <address@hidden>
---
 v2: Use "-Wno-error" instead of "-fgnu89-inline"

 configure | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/configure b/configure
index 2b9ba7d..9514533 100755
--- a/configure
+++ b/configure
@@ -4562,6 +4562,11 @@ if test "$libiscsi" != "no" ; then
     libiscsi="yes"
     libiscsi_cflags=$($pkg_config --cflags libiscsi)
     libiscsi_libs=$($pkg_config --libs libiscsi)
+    if $pkg_config --exact-version=1.9.0 libiscsi; then
+      # There are some bad inline declarations in scsi-lowlevel.h of
+      # libiscsi 1.9.0 which don't work in gnu99 mode, so we need this:
+      libiscsi_cflags="-Wno-error $libiscsi_cflags"
+    fi
   else
     if test "$libiscsi" = "yes" ; then
       feature_not_found "libiscsi" "Install libiscsi >= 1.9.0"
-- 
1.8.3.1